RFR: 8146948: Add help information to log tags

[Marcus Larsson]

On 05/04/2016 12:03 PM, Ioi Lam wrote:
> The changes look good to me, but maybe the bug title "Add help 
> information to log tags" needs to changed?
>
> When I filed the bug, my main question was "what the heck is ihop", 
> and the new output is "you can use ihop with gc+ergo", which doesn't 
> really answer my question.

Fair point. I can update the title to "Enable listing of LogTagSets and 
add support for LogTagSet descriptions", if no one else has a better 
suggestion.

As is mentioned in the bug, the meaning of each tag depends on the 
context it is used in, and so ideally there will be some tagset 
description explaining the meaning of non-obvious tags.

Thanks,
Marcus

>
> Thanks
> - Ioi
>
> On 5/4/16 2:38 AM, Marcus Larsson wrote:
>> Hi,
>>
>> Need a Review for this.
>>
>> Rebased the webrev to jdk9/hs in place.
>>
>>
>> Thanks,
>> Marcus
>>
>> On 04/14/2016 03:48 PM, Marcus Larsson wrote:
>>> Hi,
>>>
>>> Please review the following patch to add descriptions to logging 
>>> tagsets.
>>>
>>> Summary:
>>> Tagsets may now be given a description in 
>>> logTagSetDescriptions.inline.hpp. All described tagsets are listed 
>>> in the -Xlog:help output as well as in the 
>>> LogConfiguration::describe output. The patch also adds trace level 
>>> logging that lists *all* tagsets in the VM (-Xlog:logging=trace). 
>>> The previous 'logging=trace logging' has been moved to 'logging=debug'.
>>>
>>> Example log output:
>>>
>>> ...
>>> [0.544s][debug][logging] Described tag combinations:
>>> [0.544s][debug][logging]  logging: Logging for the log framework itself
>>> ...
>>> [0.544s][trace][logging] All available tag sets: arguments, 
>>> biasedlocking, classinit, classload, classload+constraints, 
>>> classload+preorder, classloaderdata, classpath, classresolve, 
>>> classunload, constraints, defaultmethods, ergo, exceptions, gc, 
>>> gc+age, gc+alloc, gc+alloc+region, gc+barrier, gc+bot, 
>>> gc+classhisto, gc+classhisto+start, gc+compaction, gc+cpu, gc+ergo, 
>>> gc+ergo+cset, gc+ergo+heap, gc+ergo+ihop, gc+ergo+refine, 
>>> gc+freelist, gc+freelist+census, gc+freelist+stats, gc+heap, 
>>> gc+heap+coops, gc+heap+exit, gc+heap+region, gc+humongous, gc+ihop, 
>>> gc+jni, gc+liveness, gc+marking, gc+marking+start, gc+metaspace, 
>>> gc+metaspace+alloc, gc+metaspace+freelist, gc+phases, 
>>> gc+phases+start, gc+phases+task, gc+phases+verify, 
>>> gc+phases+verify+start, gc+plab, gc+promotion, gc+ref, gc+ref+start, 
>>> gc+refine, gc+region, gc+remset, gc+remset+exit, gc+remset+scrub, 
>>> gc+scavenge, gc+start, gc+state, gc+stats, gc+stringdedup, 
>>> gc+stringtable, gc+survivor, gc+sweep, gc+task, gc+task+stats, 
>>> gc+task+thread, gc+task+time, gc+tlab, gc+verify, gc+verify+start, 
>>> gc+workgang, heap+ergo, itables, jfr, jfr+instrumentation, 
>>> jfr+types, logging, logging+test, modules, monitorinflation, 
>>> monitormismatch, os, os+cpu, os+thread, pagesize, protectiondomain, 
>>> ref, safepoint, safepointcleanup, stacktrace, startuptime, 
>>> verification, vmoperation, vtables
>>>
>>>
>>> Webrev:
>>> http://cr.openjdk.java.net/~mlarsson/8146948/webrev.00/
>>>
>>> Issue:
>>> https://bugs.openjdk.java.net/browse/JDK-8146948
>>>
>>> Testing:
>>> Internal VM tests through RBT
>>>
>>> Thanks,
>>> Marcus
>>>
>>
>